The M6.7 earthquake (Figure 1) that struck Surigao City on 10 February 2017 caused a 2D shift in the coordinates[1] by as much as 12.9 cm in the north-west direction (Figure 2). This displacement (10.1 cm to North, 8.0 cm to West, and 2.8 cm Down) (Figures 3, 4, and 5, respectively) was measured from 09 to 11 February 2017 from the active geodetic station (AGS) PSUR of PageNET, which is located in Surigao City, 14km from the earthquake’s epicenter. The next nearest AGS PTGO in Tagoloan, Misamis Oriental, which is 158 km from the epicenter, showed no significant shift in its position.

The data from PSUR was processed using Bernese GNSS[2] Software from 01 to 20 February 2017 (10 days before and after the event) using the best available products (e.g. orbits, clocks) from the International GNSS Service (IGS). The displacements measured are not fixed to a stable tectonic plate and are just based solely on the change in position in the ITRF. The reference coordinates of the stations are based on the May 2015 monthly solution from Bernese.

Continuous monitoring of the stations is ongoing for post-earthquake events.

[1]Coordinates in the International Terrestrial Reference Frame (ITRF) 2008

NAMRIA produces topographic maps that are used as base maps for other thematic maps like land cover, land condition, land
classification, cadastral, etc. In addition, we have digital data of road maps available. This data comes from the Department of Public Works and Highways (DPWH).